Downtime Analysis Research Articles

Perancangan Sistem Integrasi Sparepart Menggunakan Aplikasi Macro Visual Basic for Aplication Excel

This research aims to design a spare part integration system using a VBA Excel application as a solution to expedite the search process in a spare part warehouse in Tangerang. The main problems encountered include lengthy search times due to disorganized layouts and the absence of an adequate support system. The methods used include downtime analysis, redesign of spare part rack layouts, and development of a VBA-based search application. The results show that the proposed system significantly reduces spare part search times and improves the warehouse's operational efficiency (Integration system, spare parts, VBA Excel, efficiency.).

A method for assessing the characteristics of the virtual machine migration process, taking into account the type of migrations and applications

Dynamic resource allocation in cloud computing is a critical aspect. It is necessary for computing resources scaling to maintain application performance, reduce costs and ensure the reliability of IT systems. Dynamic resource allocation is possible using open virtual machines (VM), but live migration is a relatively expensive and resource-intensive operation. A number of VM migration algorithms have been proposed, each with different performance characteristics depending on the state of the host system, network, and the VM workload. Recently, a large number of works have emerged that have developed models for assessing the effectiveness of of VM migration, but many of them do not provide a standard of satisfactory prediction accuracy and are built for a single migration algorithm, which limits the use of data models. This work uses a statistical approach to estimate the total migration time and VM downtime based on the approximation of probability densities by Gram-Charlier and Laguerre Series. The proposed method, in comparison with the known ones, allows one to answer the question of what is the probability of total migration time and VM downtime for a given migration type and VM application. The analysis of total migration time and VM downtime is based on the Virtual Machine Live Migration Dataset includes more than 40 000 virtual machine migration records with five different live migration algorithms: post-copy migration, pre-copy migration and its modifications: CPU throttling delta compression, and data compression. The dataset includes approximately 8000 migration records of each migration algorithm with 9 types of workloads. Analysis of the results allows us to conclude that the type of application significantly influences both the shape of the empirical distribution (histograms) of total migration time and its characteristics, therefore it is advisable to obtain an analytical expression for the distribution law of the total migration time and VM downtime taking into account these circumstances. The results of the experiments shows that this method does not depend on the migration algorithm and the type of working application. The use of the Laguerre series can be recommended as giving more reliable results compared to Gram-Charlier series. A method for estimating total migration time and VM downtime can be integrated into a management system to select the best monitoring window for servers and evaluate service-level agreement terms.

EFFICIENCY OF THE ORGANIZATION OF THE MAINTENANCE POINT AT THE RAILWAY STATION

Background. The article is devoted to the description of the design modeling of the brake testing point with its further modernization into a maintenance point at a passenger station in the St. Petersburg transport hub.
 Materials and methods. Materials from open Internet sources, logistics theory, systems theory, systems approach, project modeling, economic justification, comparison “as is” and “as will be” were used.
 Results. Based on the results of the analysis of the average downtime of one train during maintenance at the service station, the economic effect was determined.
 Conclusion. Based on the results of the study, a solution was proposed for the organization of a maintenance point at the St. Petersburg – Finlandsky railway station with an appropriate feasibility study. With the application of the proposal, it is possible to improve the quality performance of the railway and optimize costs. It has been established by calculation that the presence of a technical service point at the St. Petersburg – Finlyandsky railway station will allow trains to move along a given route without the need for a secondary technical inspection at the St. Petersburg – Sortirovochny – Moskovsky station.

Early life failure modes and downtime analysis of onshore type-III wind turbines in Turkey

Operations and maintenance costs, and unplanned downtime accounts for a significant proportion of the total expenditure of windfarms. Therefore, reduction of these costs is essential, which requires a better understanding of the wind turbines' reliability in terms of failure rates and downtime with operational lifetime. Failure rates and downtime are generally logged using condition monitoring systems, which mainly focus on Supervisory Control and Data Acquisition (SCADA) alarm signals. The aim of this paper is to use SCADA alarm statistics to provide a new failure rate and downtime survey and thus to evaluate reliability performance of the major wind turbine components and subsystems. The paper focuses on a modern onshore windfarm located in Turkey with Type-III wind turbines over the course of the first two years of operations, which is the first time reliability data from Turkey has been published in literature.

Liquefied natural gas plant maintenance: a case study of gas turbine centrifugal compressor thrust bearing failure analysis

Maintenance is essential for preserving gas turbine engineering system functionality during equipment life cycle. Heavy-duty gas turbine (HDGT) engineering systems are often quite complex to maintain. Therefore an effective condition based maintenance (CBM) program is vital to reduce downtime, improve equipment reliability and cost optimization. It is estimated that 50 to 75% of gas turbine maintenance cost is related to the replacement and repair of hot section parts. Furthermore, the maintenance intervals of the engine is governed by the hot section material durability, and the replacement of these components is the largest contributor to determining maintenance related equipment availability. This paper investigate multiple thrust bearing failures on gas turbine driven centrifugal compressor application in a liquefied natural gas (LNG) plant. A root cause failure analysis (RCFA) approach was conducted to determine the failure mode and its consequencies. Process instability is believed to be the cause of several thrust bearing failures. Downtime analysis is presented to estimate the the loss of production (LPO).

Downtime analysis of a vegetable oil manufacturing company: A case study

Downtime analysis of a vegetable oil manufacturing company: A case study

Assessment of Straight-Line Drawing Machine and Workforce Utilization Using Time Study, Work Sampling and Downtime Analysis in Steel Industry

Assessment of Straight-Line Drawing Machine and Workforce Utilization Using Time Study, Work Sampling and Downtime Analysis in Steel Industry

Assessment of Current Downtime Analysis

Abstract: The approach used to calculate downtime for complicated projects is consistent with the literature: simulation. Researchers evaluate current downtime study on Shipping Corporation in this report. As a result, the existing approach for determining downtime for complex projects is untrustworthy; in fact, due to the significant simulation uncertainty, it is highly unsafe to utilise current methodology to make predictions on downtime distribution. We advocate utilising a stochastic metocean condition generator in the simulation to reduce simulation uncertainty. These uncertainties, however, may be managed by the model used, & they can also be quantified. Finally, a comparison1should be drawn between simulation uncertainty in HADDOCK & combined model, parametric, & simulation uncertainty in a stochastic model simulation. Keywords: Marine operation, downtime analysis, Assessment advantages and limitations

Evaluation of the use of the bedding function of City Clinical Hospital No. I. Pirogov during the period 2012–2021 based on statistical indicators

Relevance. The importance of efficient use of internal resources in health care is recognized at all levels of health management. An analysis of the indicators of the bed fund in dynamics makes it possible to assess the resources of a medical organization, identify problematic aspects in time and develop a set of measures aimed at eliminating errors and optimizing the work of the institution. Purpose of the study. Evaluation of the performance indicators of the round-the-clock hospital of the City Clinical Hospital No. 1 named after N. I. Pirogov in the period 2012–2021 in order to improve the efficiency of the medical organization. Materials and methods. To achieve the goal of the study, the obtained material was processed using analytical and statistical methods. Indicators of the use of the bed fund of the City Clinical Hospital No. 1 named after N. I. Pirogov for 2012–2021, necessary for calculations, were taken from table 3100 of the Federal statistical Obstrvation form No. 30 “Information on a medical organization”. The calculation of indicators was carried out on the basis of methodological recommendations on the application of standards and norms of resource provision of the population in the healthcare sector [1]. Results and discussions. To assess the effectiveness of a medical organization providing care in a hospital, 4 main indicators of the use of the bed fund were used. The results of the average annual bed occupancy showed that the highest level of the indicator falls on 2014 (404 days), and the lowest on 2021 (278 days). The indicator tended to decrease by 24 % and amounted to 278 days by 2021, which indicates a pronounced intensification of the treatment process. The bed turnover indicators indicate a pronounced intensification of the treatment process. The greatest intensification was recorded in 2021 (43.9 patients per 1 bed) and amounted to 129 %. In general, the bed turnover indicators for the hospital in the period from 2012–2021. had an upward trend. An analysis of the bed turnover clearly showed that a two-fold excess of the standard significantly affected the average duration of the patient's stay in bed. In 2012, the indicator was 10.5 days. In subsequent years, the indicator tended to decrease and by 2021 reached the level of 4.9 days. The results of the analysis of bed downtime show that the most downtime of beds occurs in 2020 (1.6 days) and 2021 (1.5 days). Such a jump in the indicator is most likely associated with the forced of beds re-profiling. Conclusions. Analysis of indicators of the use of beds in the City Clinical Hospital No. 1 named after N. I. Pirogov in the period 2012–2021. showed that in general there is an increase in the efficiency of the hospital. Therefore, it is necessary to constantly analyze the main statistical indicators in order to identify errors early and develop ways to solve them.

The Application of Taguchi-WSM, Taguchi-WPM and Taguchi-WASPAS Multicriteria Methods to Optimize Downtime in a Production Process

In the industrial transformation of animal feed for chickens, downtime analysis is a crucial part of the plant's operations. Unfortunately, the literature on downtime analysis has a serious shortcoming; it fails to link downtime with Taguchi method’s optimization and ranking. To correct this deficiency, this paper proposes a new method that couples the Taguchi scheme with the weighted sum method (WSM), weighted product method (WPM) and weighted aggregated sum product assessment (WASPAS) method. A new model was developed to contain downtime factors, levels, orthogonal matrix, signal-to-noise proportions, normalisation indices, criteria weights and preference scores. The results of the Taguchi-WSM, Taguchi-WPM and Taguchi-WASPAS show that workstation 2 has the highest rankings of 0.8446, 8.9090 and 4.8770 for the Taguchi-WSM, Taguchi-WPM and Taguchi-WASPAS, respectively. Also, the lowest rankings of 0.1553, 6.7990 and 3.4800 were recorded for workstation 1 using the Taguchi-WSM, Taguchi-WPM and Taguchi-WASPAS methods, respectively. However, from literature reports, WASPAS has been associated with the best results compared to WSM and WPM. Hence, from the various results of prioritizing workstations 1 and 2, the results of the Taguchi-WASPAS method are recommended. This is the first time the downtime problem for animal feed processing equipment will be approached by a joint optimization and ranking with the Taguchi scheme, WSM, WPM and WASPAS multicriteria methods.

Reduction of equipment unplanned downtime during repairs and modernization based on strength analysis

In order to identify bottlenecks in the equipment operation and accumulate data for the development of organizational and technical measures to reduce unplanned equipment downtime, JSC “Vyksa Metallurgical Plant” keeps records of downtime of the main technological equipment. All equipment downtime is recorded by production personnel in the automated analysis system of the workshop. Reliability specialists in the workshops have classified all units into criticality categories, which are presented in the form of a matrix that includes two groups of indicators: 1) severity of the consequences – personnel safety, safety of equipment and environment, production losses, troubleshooting costs; 2) probability of occurrence – high, medium, low, or very low. When determining the criticality assessment of an equipment unit, the most critical case of equipment failure and the worst one are considered. Classification of equipment by criticality categories is used to rank equipment in terms of reliability. The article considers the criteria for operability of machine parts, as well as the main software complexes for strength analysis that exist today. Two have been selected that will be used as strength analysis tools. The analysis of equipment unplanned downtime due to the destruction of parts was carried out on the example of the wheel rolling shop of JSC “Vyksa Metallurgical Plant”, unloaded from the shop automatic analysis system. The authors proposed the directions of application of the selected strength analysis tools and made the strength analysis of equipment parts in order to increase their structural reliability. An assessment of the potential economic effect of introduction of strength analysis tools showed the feasibility of using this innovative approach leading to downtime reduction.

P19 - Analysis of unscheduled downtime and most frequent breakdowns in a single institution

P19 - Analysis of unscheduled downtime and most frequent breakdowns in a single institution

An improved model for fast and reliable harbour wave agitation assessment

This study presents the new advances achieved in the field of harbour agitation climate assessment. Based on the improvement of an elliptic mild-slope model (MSP), which realistically reconstructs waves inside any-sized basin, represented by high-detailed unstructured meshes, and forced by real-shaped outer spectral data. A new solver is proposed for high performance runs, which allow fast agitation hindcast for statistical downtime analysis within an iterative and multi-scenario approach. Also, a realistic assimilation of partial reflection processes in quays/docks/wharfs/breakwaters is proposed. The model has been successfully validated in several harbours of special relevance in Spain with in situ measurements, through the assimilation of the hybrid downscaling (Camus et al., 2011) technique combined with monochromatic-based wave spectral reconstruction.

Maintenance Performance Evaluation and Downtime Analysis of Manufacturing Equipment in a Food Manufacturing Company

In food manufacturing, maintenance of manufacturing equipment is one of the most important essentials for an efficient manufacturing as this sector continuously face challenges that makes maintenance very critical due to the nature of manufacturing, thus as a result food manufacturing companies must add or modify their maintenance strategies in order to keep production running efficiently. The aim of this study is to carry out a maintenance performance evaluation and downtime analysis in a food manufacturing company and suggest areas for further improvement. In this study, an empirical case study was carried out in order to evaluate the maintenance performance and downtime analysis. Overall equipment effectiveness and Pareto analysis were used to carry out a maintenance performance evaluation and downtime analysis on the manufacturing equipment using three years historical data obtained from the food manufacturing company as an industrial case study. The study found that the average overall equipment effectiveness is 55.30% which is a low value when compared with Overall Equipment Effectiveness world standards, meaning that the manufacturing organisation is operating in an average condition and there is a required urgent improvement of maintenance policies and strategies, otherwise it will be difficult for the manufacturing organisation to sustain it. Thus it is necessary that in order to improve productivity, the manufacturing organisation under study should look into its manufacturing strategies so that urgent improvement of maintenance policies and strategies can be implemented and adopted.

Failure data analysis for preventive maintenance scheduling of a bottling company production system

Equipment breakdown adds to the cost of production and considerably affect the overall equipment efficiency in automated lines due to unplanned downtime. Preventive maintenance with appropriate actions has been considered to enhance products quality, equipment reliability and minimize the probability of system brake down or failure. To this end, this study conducted a reliability status of nine packaging facilities, from the perspective of existing failure data of production system in the Nigerian multinational bottling plant. Failure data of the production system were stratified and analyzed to achieve the failure interval of each of the facilities and the sub-systems. Stratification of failure data resulted to an established input format that fitted the Pareto chart analysis, Weibull Distributions and Reliability/Failure Time analysis. The results showed that the facility with minimum value of reliability was filler machine. A standby filler system was therefore recommended in order to prevent unnecessary idleness of the other facilities especially when the production target is high. The study concluded that, analysis of downtime in a production/manufacturing system assisted in predicting the likely failure interval and hence a preventive maintenance scheduled was proposed.

Process audit in a beverage industry - line efficiency and downtime analysis, a case study

Continuous improvement is the sustaining force for a company to ever stand in the market in every perspective. Particularly in the production process, a steady, quick and flexible flow has to be ma...

ДЕЯКІ АСПЕКТИ ПІДВИЩЕННЯ ЕНЕРГОЕФЕКТИВНОСТІ РОБОТИ ШАХТНИХ ВІДЦЕНТРОВИХ НАСОСІВ

Mine drainage systems, which are used at the main drainage of mining enterprises, have a drive capacity of up to 1600kW. To reduce non-productive energy losses, as well as for the continuous operation of the mining company, mine pumps must be energy efficient and reliable. Analysis of downtime of drainage systems shows that the weak point is the unloading device. This fact can lead not only to the failure of the pumping unit, but also to possible prolonged downtime of the mine. The main disadvantage of the existing disk unloading devices of mine pumps is their low reliability and low service life, due to the rapid wear of the components of the unloading unit. The most vulnerable elements of the unloading device are the unloading rings. The need for frequent replacement and adjustment of the elements of the discharge unit is associated with disassembly and assembly of the pump directly in the pump chamber. Such actions require significant costs of unproductive manual labor of service personnel, and rapid wear of parts of the unloading device necessitates their constant replenishment. Malfunctions in the unloading device can cause significant pump failures. To increase the reliability and energy efficiency of mine drainage systems, the method of control of the unloading device was used. During the experimental studies it was found that cavitation phenomena during the operation of pumping units are absent and, accordingly, can not be the cause of wear of the elements of the unloading unit. When the pumps are operating in steady state, the displacement of the rotors was monitored for 3-4 hours on each pump unit. After data processing, it was obtained that the wear of the surface of the unloading rings occurs at a rate of 0.05-0.15mm in one hour. To determine the wear of the rings of unloading during start-up - stop of the pump, at first the indicators of measuring devices at the established mode of operation of the pump unit were fixed. Then the pump was turned off and on again. After starting the pump unit, we made sure that the operating mode of the unloading device did not change and compared the readings of the shaft position indicator before stopping and after starting the pump. From the measurements made it followed that stopping and starting the pump does not lead to noticeable wear of the unloading device. Therefore, it can be assumed that mainly the wear of the discharge rings occurs during the steady operation of the pump unit.

Determinants of lost theatre capacity.

Secondary care Trusts nationwide are continuing to fail the 18-week referral to treatment (RTT) target despite several initiatives to improve theatre efficiency (2018 NHS England review). A limitation of wasted theatre productivity is required to alleviate pressures on waiting lists. Productivity, which is a measure of treatment time as a proportion of available/allocated time, takes into consideration variations in operator performance, early (non-funded) theatre starts, and over-run, and its analysis enables the determination of theatre downtime and lost theatre capacity. We monitored productivity over a 12-week period and performed downtime analysis as reported in the NHS Improvement national audit (NHSI). Results showed a marked but predictable variation in productivity connected to turnaround and session list scheduling. Productivity and booking efficiency correlated uniformly (Pearson's r=0.82). Theatre downtime was analysed with respect to three components defined in the NHSI national audit: late starts, early finish, and turnaround. We found that lost theatre time was predominantly due to early finishes; late starts were infrequent. Transport time correlated unfavourably with productivity (Pearson's r=-0.29, p=0.037) and over-run (r=0.44), and prolonged transport times were shorter when surgery was performed in a dedicated day surgery unit. Calculating the mean transport times for lists with high compared with low productivity helped us set a benchmark for patient transport times for future audit.

Analysis of Stoppages in the Process of Roadway Drivage Caused by Exceeding the Maximum Allowable Level of Methane Concentration

Abstract Methane is one of the most dangerous gases occurring in mining production. Being inseparably connected with the rock mass, it presents a serious risk to occupational safety and reduces the effectiveness of mining production. A particularly high methane hazard occurs directly during exploitation in longwall headings and the drivage of roadways. Exceeding the maximum allowable level of its concentration in these headings makes it necessary to disconnect all machines until this concentration level is reduced. This leads to unscheduled downtimes of such machines, thus increasing the costs of their operation and decreasing their effectiveness. The paper demonstrates the results from the analysis of machine downtimes in the drivage of roadways, caused by excessive methane concentration levels. The analyses were based on the indications from the system for automatic monitoring of the ventilation parameters in this heading. The results obtained clearly demonstrated that exceeded values of methane concentration caused a series of unexpected downtimes in the drivage process. As a result, the process was disturbed and its effectiveness reduced. The presented analyses are one of the first to address the issue of how methane emissions affect machine downtimes. However, this phenomenon represents a major problem that needs to be addressed comprehensively in order to minimise the losses arising out of the necessary disruptions to the exploitation process.

Reducción de tiempos muertos en operación de corte de agujeros de ventilación, en estampado de rines de acero

A company’s productivity improvement is multi-causal, one of the causes being the reduction of time. That is why this article presents the methodology that a transnational automotive company performs to reduce downtime in the ventilation hole cutting operation, since it is a critical process that directly affects the productivity of the company. This project was carried out with the DMAIC methodology, in which the diagnosis is made through Ishikawa and Pareto, continuing the analysis of time. As part of the analysis of downtimes, the most frequent failures are included, as well as preventive maintenance and specifically tooling. Information is presented regarding the areas of opportunity, implementation of improvement strategies delimited by the design of an awl. Finally, it shows the reduction of time in the change of tooling, through the implementation of the improvements.